Synchronizing valves

ABSTRACT

A synchronizing valve, for controlling the flow of fluid to and from two fluid pressure actuated components so as to synchronizing their movements, in which a housing incorporates two relatively movable members, one member being provided with a cam profile and being arranged to be operatively connected to one fluid pressure actuated component so that movement of the component causes corresponding movement of the member and the other member being provided with a cam follower and similarly being arranged to be operatively connected to the other fluid pressure actuated component. Relative movement of the two members and hence of the cam profile and follower, resulting from nonsynchronous movement of the fluid pressure actuated components, is arranged to actuate a flow proporting valve means positioned within the housing thereby adjusting the flow of fluid to or from the fluid pressure actuated components to re-establish synchronous movement.

United States Patent 1 1 3,823,646

Wadsworth July 16, 1974 SYNCHRONIZING VALVES Primary Examiner-Paul E.Maslousky [76] Inventor: Geoffrey Wadsworth, 0/0 Fort Attorney, Agent,or Firm-Stevens, Davis, Miller &

Dunlop, Erdington, Birmingham Mosher B24 9Qt', England 22 Filed: May 17,1972 [57] ABSTRACT I A synchronizing valve, for controlling the flow offluid [21] Appl 254,097 to and from two fluid pressure actuatedcomponents so as to synchronizing their'movements, in which a [30] F r iA li ti P i it D t housing incorporates two relatively movable members,M a 26 Great Britain 17080/71 one "member being provlded with a camprofile and y being arranged to be operatively connected to one [52] U 5Cl 91/171 60/97 E fluid pressure actuated component so that movement[51] Flsb H/22 of the component causes corresponding movement of [58]Fieid 60/97 E the member and the other member being provided with a camfollower and similarly being arranged to be 56] References Citedoperatively connected to the other fluid pressure actuated component.Relative movement of the two mem- UNITED T S PATENTS bers and hence ofthe cam profile and follower, result- 2,365,095 12/1944 Miller et al.91/171 non-synchronous movement of the pres- 3,2 3,333 {282; i 15? 3:;sure actuated components, is arranged to actuate a e a ""f flowproporting valve means positioned within the gggggi I 5:323 ga housingthereby adjusting the flow of fluid to or from the fluid pressureactuated components to re-establish synchronous movement.

5 Claims, 5 Drawing Figures SUPPLY PRESSURE PATENTEDJUL 1 619143,823,646

SHEET 1 or 5 SUPPLY PRESSURE FIGI.

PATENTEDJUU 61914 sum 2 or s 3.823.646

SHEET ,3 OF 5 MOI in S Mm PATENTEDJUHBIQH Y 3.823.646

sum u [1F 5 FIC14.

JUU slam 3823.646

sum 5 or 5 FIG. 5.

SYNCHRONIZING VALVES This invention relates to synchronizing valves,that is. valves for controlling the flow of fluid to and from two fluidpressure actuated components thereby synchronizing their movements.

One object of the present invention is to provide an improvedsynchronizing valve.

According to one aspect of the present invention a synchronizing valvefor controlling the flow of fluid to and from two fluid pressureactuated components so as to synchronize their movements comprises ahousing incorporating two relatively movable members, one member beingprovided with a cam profile and being arranged to be operativelyconnected to one fluid pressure actuated component so that movement ofthe component causes corresponding movement of the member and the othermember being provided with a cam follower and similarly being arrangedto be operatively connected to the other fluid pressureactuatedcomponent, relative movement of the two members and hence of the camprofile and follower, resulting from non-synchronous movement of thefluid pressure actuated components, being arranged to actuate a fluidflow control valve (more. particularly a flow proportioning valve meanspositioned within the housing) thereby adjusting the flow of fluid to orfrom the fluid pressure actuated components to re-establish synchronousmovement.

The present invention also provides asynchronizing system incorporatinga synchronizing valve in accordance with the present invention.

One embodiment of the present invention will now be described by way ofexample with reference to' FIGS. 1 to of the accompanying drawings inwhich:

FIG. 1 is a diagrammatic representation of a synchronizing system inaccordance with the present invention;

FIG. 2 is a longitudinal section through a synchronizing valve inaccordancewith the'present invention;

,FIG. 3 is a longitudinal section on the line A- A of FIG. 2;

FIG. 4 is an outside part-sectional view of the synchronizing valveshown in F IGS. 2 and 3 showing a typical cam profile and followerarrangement, and

FIG. 5 is a further outside view of the synchronizing valve shown inFIGS. 2 to 4 showing a typical valve inlet and outlet arrangement.

A system for synchronizing the movement of two hydraulically operatedaircraft airbrake flaps 41 and 42, as shown in FIG. 1, comprises a pairof rams 43,44 one arranged to actuate each flap and a synchronizingvalve 45 arranged to control the flow of hydraulic fluid to each ram.Flow of fluid to the ends 72 and 73 of rams 43 and 44 respectively isarranged to extend the rams and associated airbrake flaps while the flowof fluid to the other ends 74 and 75 of the rams is arranged to retractthe rams and flaps. A selector valve 46 controls the flow of fluid froma source of supply pressure (not shown) to the synchronizing valve 45and also controls the exhaust of fluid from the synchronizing valve 45to a fluid reservoir 47.

Each airbrake flap is linked to a separate rotatable shaft membersupported by and partially enclosed within the housing of synchronizingvalve 45.

In the example shown in FIG. 1 each airbrake is linked to thesynchronizing valve by a system of levers 48,49. It will be understoodthat any other suitable form of mechanical linkage, such as wires,pulleys,

gears or rods. or indeed any suitable form of hydraulic or pneumaticfeedback may be employed. Airbrake flap 41 is linked by rod 48 to aninner rotatable shaft member 16 (see FIG. 2) supported within thehousing 8 of synchronizing valve 45 by hearing 33 and airbrake flap 42is linked by rod'49 to an outer rotatable shaft member 15 supportedcoaxially with shaft member 16 on bearing 19 by bearing housing 12.

Inner shaft member 16 carries a roller shaft member 37 extending atright angles thereto. The end of roller shaft member 37 remote fromshaft 16 carries a roller bearing 35 which acts as a cam followerco-operating with a cam profile cut-out 50 (see FIG. 4) in the end ofouter rotatable shaft member 15 within housing 8.

The end of inner shaft member, 16 within housing 8 is connected to avalve spool 25 by means of a cylindrical connector 51 arranged to fitover the ends of the spool and inner'shafucylindrical connector 51 beingpinned to the inner shaft by roller shaft 37 and to the spool by aseparate transversely extending pin 21. Thus relative rotation of innerand outer shaft members 16 and 15 causes relative movement of rollerbearing 35 and cam profile 50 thereby causing corresponding axialdeflection of spool 25. v

Spool 25, which is provided with an axially extending internal bore 52is arranged to extend within a bore 53 of the housing, each end of thespool being provided with an annular seal 24 to prevent the escape offluid between the spool and bore 53 into the remainder of the housing.The portion of spool 25 which extends between the seals 24 is of areduced diameter and is provided with two axially spacedcircumferentially extending flanges 54 and 55 which thus form threeannular passageways 56, 57 and 58 between spool 25 and bore 53. Theexternal diameter of flanges 54 and 55 is arranged to be such that theycan make sealed contact with bore 53 in a manner to be described.

Bore 53 is provided with four axially spaced circumferentially extendinggrooves 59, 60, 61 and 62. Groove communicates via passageway 63,springloaded non-return valve 5 and passageway 64 with combined inletand outlet passage 65 which in turn communicates with combined inlet andexhaust port (see FIG. 5). Groove 62 also communicates via passageway66, spring-loaded non-return valve 9 and passageway 67 with combinedinlet and outlet passage 65.

I and 58 in communication with otherwise closed internal bore 52.

Non-return valves 5 and 9 which .are directly connected by passageway 64are arranged so that when the synchronizing valve is supplying fluid tothe ends 72,73 of the rams 43 and 44, in order to extend the airbrakeflaps, the direct flow of fluid through passageway 64 is prevented bynon-return valve 5.

A centralizing pin 18 (see FIGS. 3 and 4) extending through alignedtransversely extending holes 76,77 in the exposed ends of shafts and 16is provided to enable the bearing 35 to be centralized within camprofile cut-out 50 during installation ofthe synchronizing valve andfinal adjustment of the feedback levers 48,49. Centralizing pin 18 isremoved during operation of the valve and stored in hole 78 in housing8.

The system functions as follows:

Thepilot selects the airbrakes extend condition using selector valve 46.This connects the supply pressure to synchronizing valve 45 and hence tothe ends 72 and 73 of rams 43 and 44 respectively while connecting theother ends 74 and 75 of the rams to fluid reservoir 47.

As flaps 41 and 42 extend, their movement is fed back to synchronizingvalve 45 via links 48 and 49 and results in a clockwise rotation ofinner and outer shafts l6 and 15.As long as flaps 41 and 42 extendsymmetrically, that is in synchronism, shafts 16 and 15 will'rotate in aclockwise manner without relative movement therebetween and bearing 35thus remains in the center of cam profile cut-out 50 thus maintainingspool 25 in its axially central position in which equal quantities offluid flow to rams 43 and 44 via ports 68 and 69 respectively. The fluidflows to outlets 68 and 69 via passages 65 and 67, non-return valve 9,groove 62, passageways 56,57 and 58, drillings 70 and 71, bore 52 andgrooves 59 and 61.

lf flap 41 extends ahead of flap 42 then inner shaft 16 will rotaterelative to outer shaft 15 causing bearing 35 to move along the camprofile thereby drawing spool 25 to the right, as viewed in theaccompanying drawings. This movement of the spool to the right causesflanges 55 and 54 to move to the right in grooves 60 and 62 respectivelythereby reducing or completely cutting-off the communication to internalbore 52 via drillings 70 and 71 thus reducing or cutting-off the flow offluid to outlet 68 while increasing the flow of fluid to outlet 69 viaannular passageway 57.

The amount of movement of the spool 25 in response to a given amount ofmovement of the airbrake flaps 41 and 42 is determined by the shape of.the cam profile cut-out 50- and by the arrangement of the feedbacklinkages 48 and 49. Typically the system is arranged so that one degreemovement of either airbrake flap results in a one degree rotation of theassociated inner or outer shaft member and the cam profile cut-out is sodesigned that three degrees relative rotation between the inner andouter shaft members is sufficient to completely cut off the flow offluid to one outlet while allowing the full flow to the other outlet.The cam profile cut-out shown in the accompanying drawings is arrangedto allow up to 65 degrees relative rotation between the inner and outershaft members in either direction, though after 3 degrees relativerotation the flow of fluid to one outletis completely cutoff asdescribed above.

The reducing or cutting-off of the flow of fluid-to outlet 68 andincreasing of the flow to outlet 69 reduces or eliminates the rate ofextension of flap 41 and allows ram 44 to catch up ram 43 thusre-establishing synchronization between the movements of flaps 41 and 42thereby eliminating the relative rotation between inner and outer shafts16 and 15 and returning bearing 35 to the centre of cam profile cut-out50.

Should flap 42 extend ahead of flap 41 outer shaft member 15 rotatesrelative to inner shaft member 16 and bearing 35 moves along cam profilethereby pushing spool 25 to the left, as viewed in the accompanyingdrawings. This movement of the spool to the left causes flanges 54 andto reduce or completely cut off the flow of fluid to outlet 69, viaannular passage 57 while increasing the flow of fluid, via annularpassage 58, to outlet 68. This reducing or cutting-off of the flow offluid to outlet 69 allows ram 43 to catch up ram 44 thus re-establishingsynchronization between the movements of flaps 41 and 42 and returningbearing 35. to the center of cam profile cut-out 50.

Thus the extension of airbrake flaps 41 and 42 is controlled by thesystem and the occurrance of dangerous excessive assymmetry is'avoided.

When the pilot selects the airbrakes retract condition selector valve 46connects the ends 74 and 75 of rams 43 and 44 directly to the fluidpressure supply and connects the ends 72 and 73 of the rams to fluidreservoir 47 via synchronizing valve 45. Thus by controlling the rate ofexhaust of rams 43 and 44 using synchronizing valve 45 the retraction offlaps 41 and 42 can be synchronized in a similar manner to theirextension.

As long as flaps 41 and 42 retract symmetrically inner and outer shafts16 and 15 rotate in an anticlockwise manner without relative movementtherebetween and bearing 35 again remains in the center of cam profilecut-out 50 thus maintaining spool 25 in its axially central position inwhich equal quantities of fluid are exhausted from rams 43 and 44. Thefluid flows to combined inlet and outlet passage from outlets 68 and 69via grooves 59 and 61, annular passageways 56, 57 and 58, drillings and71, bore 52, passageway 63, non-return valve 5 and passageway 64.Non-return valve 9 prevents the direct flow'of fluid, via passages 66and 67, into passage 65.

1n the event of assummetrical retract of the flaps the shaft members 15and 16 will rotate anti-clockwise relative to each other and cause theappropriate axial movement of spool 25 to control the relative rates ofexhaust of fluid from rams 43 and 44 in a similar mannet to the controlof the extension of the flaps described above. Thus the retraction ofthe airbrake flaps is controlled by the system and the occurrance ofdangerous excessive assymmetry is again avoided.

Although the synchronizing valve described above incorporates a spoolvalve member arranged to be axially displaced in response to relativemovement between a cam and a follower resulting from relative rotationbetween two co-axial shaft members, the synchronizing valve couldequally well be arranged to operate any convenient form of fluid flowcontrol valve, other than a spool valve, in response to relativemovement between a cam and a follower resulting from nonrotationalrelative movement between two relatively movable members.

Further, although the synchronizing system has been described above withreference to the control of hydraulically actuated aircraft airbrakeflaps it will be appreciated that the system has a wide field ofapplication in the synchronization of the control of the movement ofhydraulically and pneumatically actuated components in general.

1 claim:

l. A synchronizing valve assembly for controlling the flow of fluid toand from two fluid pressure actuated components so as to synchronizetheir movements comprising:

a. a housing having two relatively movable members comprising inner andouter rotatable shaft members mounted co-axially with one inside theother, one member having a cam profile integrally arranged to beoperatively connected to one fluid pressure actuated component so thatmovement of the component causes movement of said one member;

b. the other member having a cam follower and similarly arranged to beoperatively connected to the other fluid pressure actuated component;

c. a flow proportioning valve means positioned within the housing andmeans connecting said members to said valve so that relative rotation ofthe two shaft members along with the cam profile and follower whichresults from non-synchronous movement of the fluid pressure actuatedcomponents will cause the valve to adjust the flow of fluid to or fromthe fluid pressure actuated components to re-establish synchronousmovement.

2. An assembly according to claim 1 wherein the cam follower comprises aroller mounted on a shaft carried by and extending at right angles tothe inner rotatable shaft member.

3. An assembly according to claim 2 wherein the cam profile comprises aslot cut in the outer rotatable shaft member and arranged to receive theroller.

4. An assembly according to claim 1 wherein the flow proportioning valvemeans comprises a spool valve member axially slidable within a boreinthe housing, relative movement between the two relatively movablemembers being arranged to axially displace the spool valve within thebore thereby adjusting the flow of fluid to or from the fluid pressureactuated components.

fluid communication with one annular end passageway and the other fluidpressure actuated component being arranged to be in permanent fluidcommunication with the center annular passageway, the two annular endpassages being interconnected by an internal bore extending within thespool valve member, two axially spaced circumferentially extendinggrooves provided in v the wall of the bore, the two groovescommunicating with a combined inlet and outlet passage, a non-returnvalve means disposed between the combined inlet and outlet passage andthe circumferentially extending grooves, the non-return valve meansbeing arranged to supply fluid to the fluid pressure actuated componentsvia one groove and to exhaust fluid from the components via the othergroove, the flanges provided on the spool valve member being arranged toco-operate with the grooves to allow a substantially equal flow of fluidto or from the fluid pressure actuated components when these componentsare moving in synchronism, axial displacement of the spool valve memberresulting from non-synchronous movement of the fluid pressure actuatedcomponents being arranged to allow proportionately more fluid to flow toor from oneor the other of the fluid pressure actuated componentsdepending on the direction of displacement of the spool valve member.

1. A synchronizing valve assembly for controlling the flow of fluid toand from two fluid pressure actuated components so as to synchronizetheir movements comprising: a. a housing having two relatively movablemembers comprising inner and outer rotatable shaft members mountedco-axially with one inside the other, one member having a cam profileintegrally arranged to be operatively connected to one fluid pressureactuated component so that movement of the component causes movement ofsaid one member; b. the other member having a cam follower and similarlyarranged to be operatively connected to the other fluid pressureactuated component; c. a flow proportioning valve means positionedwithin the housing and means connecting said members to said valve sothat relative rotation of the two shaft members along with the camprofile and follower which results from non-synchronous movement of thefluid pressure actuated components will cause the valve to adjust theflow of fluid to or from the fluid pressure actuated components tore-establish synchronous movement.
 2. An assembly according to claim 1wherein the cam follower compriseS a roller mounted on a shaft carriedby and extending at right angles to the inner rotatable shaft member. 3.An assembly according to claim 2 wherein the cam profile comprises aslot cut in the outer rotatable shaft member and arranged to receive theroller.
 4. An assembly according to claim 1 wherein the flowproportioning valve means comprises a spool valve member axiallyslidable within a bore in the housing, relative movement between the tworelatively movable members being arranged to axially displace the spoolvalve within the bore thereby adjusting the flow of fluid to or from thefluid pressure actuated components.
 5. An assembly according to claim 4wherein the spool valve member is supported at its ends in sealedsliding contact within the bore, the portion of the spool valve memberbetween the sealed ends being of reduced diameter and provided with twoaxially spaced circumferentially extending flanges which co-operate withthe bore to provide three axially spaced passageways between the boreand the reduced diameter portions of the spool valve member, one fluidpressure actuated component being arranged to be in permanent fluidcommunication with one annular end passageway and the other fluidpressure actuated component being arranged to be in permanent fluidcommunication with the center annular passageway, the two annular endpassages being interconnected by an internal bore extending within thespool valve member, two axially spaced circumferentially extendinggrooves provided in the wall of the bore, the two grooves communicatingwith a combined inlet and outlet passage, a non-return valve meansdisposed between the combined inlet and outlet passage and thecircumferentially extending grooves, the non-return valve means beingarranged to supply fluid to the fluid pressure actuated components viaone groove and to exhaust fluid from the components via the othergroove, the flanges provided on the spool valve member being arranged toco-operate with the grooves to allow a substantially equal flow of fluidto or from the fluid pressure actuated components when these componentsare moving in synchronism, axial displacement of the spool valve memberresulting from non-synchronous movement of the fluid pressure actuatedcomponents being arranged to allow proportionately more fluid to flow toor from one or the other of the fluid pressure actuated componentsdepending on the direction of displacement of the spool valve member.